Hellerstein S, Alon U, Warady B A
Department of Pediatrics, University of Missouri-Kansas City School of Medicine.
Pediatr Nephrol. 1992 Nov;6(6):507-11. doi: 10.1007/BF00866485.
The aim of this study was to evaluate the plasma creatinine concentration (PCr) and creatinine clearance (CCr) for estimation of glomerular filtration rate (GFR). Inulin clearance (Cin) was used as the reference standard for GFR. Thirty-nine concurrent Cin and CCr studies provided data for comparing Cin with the measured CCr and with the calculated CCr (calc-CCr). (Calc-CCr = k.L/PCr, where L = height in centimeters and k is the proportionality constant.) Thirty-one children 5.3-20.8 years of age, with Cin ranging from 2.8 to 138.8 ml/min per 1.73 m2, participated in these studies at The Children's Mercy Hospital. The measured CCr was 16.7 +/- 10.3 ml/min per 1.73 m2 (P < 0.001) greater than the Cin, and the calc-CCr overestimated Cin by a mean of 31.6 +/- 20.8 ml/min per 1.73 m2 (P < 0.001). Although there is good correlation between Cin and CCr (r = 0.96), and Cin and calc-CCr (r = 0.90), the 95% confidence intervals are quite broad. Hence, the CCr and the calc-CCr, derived using Schwartz values for k, consistently overestimate GFR. However, if the k value in the equation GFR = k.L/PCr is derived from k = Cin/L, rather than from k = CCr.PCr/L, a more accurate estimate of GFR may be obtained.
本研究的目的是评估血浆肌酐浓度（PCr）和肌酐清除率（CCr）以估算肾小球滤过率（GFR）。菊粉清除率（Cin）用作GFR的参考标准。39项同时进行的Cin和CCr研究提供了数据，用于比较Cin与测量的CCr以及计算的CCr（calc-CCr）。（Calc-CCr = k·L/PCr，其中L =身高（厘米），k为比例常数。）31名年龄在5.3至20.8岁之间的儿童参与了儿童慈善医院的这些研究，其Cin范围为每1.73 m² 2.8至138.8 ml/min。测量的CCr比Cin高16.7±10.3 ml/min每1.73 m²（P < 0.001），calc-CCr平均高估Cin 31.6±20.8 ml/min每1.73 m²（P < 0.001）。尽管Cin与CCr之间（r = 0.96）以及Cin与calc-CCr之间（r = 0.90）存在良好的相关性，但95%置信区间相当宽。因此，使用Schwartz的k值得出的CCr和calc-CCr始终高估GFR。然而，如果在GFR = k·L/PCr方程中的k值由k = Cin/L得出，而不是由k = CCr·PCr/L得出，则可能获得更准确的GFR估计值。
